Harald Clahsen’s research while affiliated with Universität Potsdam and other places

Heritage speakers (HS) have been shown to experience difficulties with inflectional morphology (particularly with irregular morphology) and to frequently overapply regular morphology. The present study seeks to get further insight into the inflectional processes of HS by investigating how these are generalized to nonce words in language production, the first study of this kind for heritage Turkish. We specifically examined morphological generalization processes in the Turkish aorist which – unusual for this language – includes both regular and irregular forms. A written elicited-production experiment containing nonce verbs with varying degrees of similarity to existing verbs was administered to Turkish HS and native monolingually-raised Turkish speakers (MS). We also explored how well a formal model that was trained on a large lexical corpus of Turkish matches the human speakers’ performance. Our main finding is that HS employ both similarity-based and rule-based mechanisms for morphological generalization of the Turkish aorist, with subtle differences to the way these mechanisms are applied by Turkish MS.

In an increasingly ageing, multilingual, and digitalised society, there is still a lack of research on older adults’ adoption and use of mobile technology for supporting their self-directed second language learning. In the present study, we investigated the extent to which seniors residing in Germany (aged 60+) engage in mobile-assisted language learning (MALL) and the factors encouraging or discouraging them from using language learning apps by conducting a web-based survey ( n = 208) and a series of in-depth individual interviews ( n = 22). Our results show that (1) participants were resistant to fully embrace the potential of MALL despite their active engagement in language learning and extensive use of digital technology, online resources, and mobile devices; and (2) self-perceived digital literacy and openness towards new developments are strong factors favouring the use of language learning apps in older adulthood. We interpret and discuss these results in the light of theoretical accounts of mobile learning and education in (older) adults, emphasising the need to consider the specific requirements of late-life learners in future implementations of language learning apps. Based on our results, we highlight several implications for designers and developers of such apps intended to facilitate full inclusion of seniors as mobile language learners.

Morphological variability in bilingual language production is widely attested. Producing inflected words has been found to be less reliable and consistent in bilinguals than in first-language (functionally monolingual) L1 speakers, even for bilingual speakers at advanced proficiency levels. The sources for these differences are not well understood. The current study presents a detailed investigation of morphological generalization processes in bilingual speakers’ language production. We examined past participle formation of German using an elicited-production experiment containing nonce verbs with varying degrees of similarity to existing verbs testing a large group of bilingual Turkish/German speakers relative to L1 German speakers. We compared similarity-based lexical extensions with generalizations of morphological rules. The results show that rule-based generalizations are used less often and more variably within the bilingual group than within the L1 group. Our results also show a selective effect of age of acquisition on the bilingual speakers’ morphological generalizations.

The current study investigates how bilingual children encode and produce morphologically complex words. We employed a silent-production-plus-delayed-vocalization paradigm in which event-related brain potentials (ERPs) were recorded during silent encoding of inflected words which were subsequently cued to be overtly produced. The bilingual children's spoken responses and their ERPs were compared to previous datasets from monolingual children on the same task. We found an enhanced negativity for regular relative to irregular forms during silent production in both bilingual children's languages, replicating the ERP effect previously obtained from monolingual children. Nevertheless, the bilingual children produced more morphological errors (viz. over-regularizations) than monolingual children. We conclude that mechanisms of morphological encoding (as measured by ERPs) are parallel for bilingual and monolingual children, and that the increased over-regularization rates are due to their reduced exposure to each of the two languages (relative to monolingual children).

Previous research has shown that heritage speakers struggle with inflectional morphology. ‘Limitations of online resources’ for processing a non-dominant language has been claimed as one possible reason for these difficulties. To date, however, there is very little experimental evidence on real-time language processing in heritage speakers. Here we report results from a masked priming experiment with 97 bilingual (Turkish/German) heritage speakers and a control group of 40 non-heritage speakers of Turkish examining regular and irregular forms of the Turkish aorist. We found that, for the regular aorist, heritage speakers use the same morphological decomposition mechanism (‘affix stripping’) as control speakers, whereas for processing irregularly inflected forms they exhibited more variability (i.e., less homogeneous performance) than the control group. Heritage speakers also demonstrated semantic priming effects. At a more general level, these results indicate that heritage speakers draw on multiple sources of information for recognizing morphologically complex words.